Surgical adhesive able to glue in wet conditions

ABSTRACT

Compositions and methods for sealing tissue of a patient in a wet environment are disclosed.

FIELD OF THE DISCLOSURE

The disclosure relates generally to surgical adhesives and sealants.More particularly, the disclosure relates to surgical adhesives andsealants suitable for application to wet surfaces.

BACKGROUND

Surgeons are routinely required to achieve hemostasis and stop bothminor and massive bleeding, particularly of highly vascularized organs.Organs are naturally wet to facilitate their motion and reduce friction,and are further wetted during surgery due to extracorporeal fluids thatare produced and use of irrigation solutions to aspirate debris, clearthe field of view, and avoid adhesion formation. However, bonding to wettissue surfaces is difficult to achieve. Current surgical adhesives andsealants often lack sufficient ability to adhere to wet surfaces.

SUMMARY

The present disclosure is directed to compositions and methods forsealing tissue of a patient under wet conditions.

In one aspect, the present disclosure provides a kit comprising: (a) adry powder composition comprising a first component having a polymercore substituted with at least two sulfhydryl groups and a secondcomponent having a polymer core substituted with at least twosulfhydryl-reactive groups; (b) a first aqueous solution comprisingL-3,4-dihydroxyphenylalanine (L-DOPA) and having a pH of about 1 toabout 5.5; and (c) a second aqueous solution having a pH of about 6 toabout 11; wherein each of (a), (b), and (c) is packaged separately priorto use.

In another aspect, the disclosure provides a composition comprising acrosslinked polymeric material having a structure:

wherein each n is independently 15 to 150; and each m is independently15 to 150.

In another aspect, the disclosure provides a composition prepared byreacting a component having a polymer core substituted with at least twosulfhydryl-reactive groups with (i) L-DOPA and (ii) a component having apolymer core substituted with at least two sulfhydryl groups.

In another aspect, the disclosure provides a kit comprising: (a) a drypowder composition comprising a first component having a polymer coresubstituted with at least two sulfhydryl groups and a second componenthaving a polymer core substituted with at least two sulfhydryl-reactivegroups; (b) a first aqueous solution having a pH of about 1 to about5.5; (c) a second aqueous solution having a pH of about 6 to about 11;and (d) L-3,4-dihydroxyphenylalanine (L-DOPA); wherein each of (a), (b),(c), and (d) is packaged separately prior to use.

In another aspect, the disclosure provides a method of sealing tissue ofa patient comprising: (a) dissolving a dry powder composition comprisinga first component having a polymer core substituted with at least twosulfhydryl groups and a second component having a polymer coresubstituted with at least two sulfhydryl-reactive groups in a firstaqueous solution comprising L-3,4-dihydroxyphenylalanine (L-DOPA) andhaving a pH of about 1 to about 5.5 to form a homogeneous solution; (b)adding a second aqueous solution having a pH of about 6 to about 11 tothe homogeneous solution to form a mixture; and (c) placing the mixtureinto contact with a tissue surface and allowing a three-dimensionalcomposition to form on the tissue.

In another aspect, the disclosure provides a method of sealing tissue ofa patient comprising: (a) treating a tissue surface with a solution ofL-DOPA to obtain a treated tissue surface; (b) dissolving a dry powdercomposition comprising a first component having a polymer coresubstituted with at least two sulfhydryl groups and a second componenthaving a polymer core substituted with at least two sulfhydryl-reactivegroups in a first aqueous solution having a pH of about 1 to about 5.5to form a homogeneous solution; (c) adding a second aqueous solutionhaving a pH of about 6 to about 11 to the homogeneous solution to form amixture; and (d) placing the mixture into contact with the treatedtissue surface and allowing a three-dimensional composition to form onthe treated tissue surface.

The foregoing summary is not intended to define every aspect of thedisclosure, and other features and advantages of the present disclosurewill become apparent from the following detailed description. Thepresent disclosure is intended to be related as a unified document, andit should be understood that all combinations of features describedherein are contemplated, even if the combination of features are notfound together in the same sentence, paragraph, or section of thisdisclosure. In addition, the disclosure includes, as an additionalaspect, all embodiments of the disclosure narrower in scope in any waythan the variations specifically mentioned above. With respect toaspects of the disclosure described or claimed with “a” or “an,” itshould be understood that these terms mean “one or more” unless contextunambiguously requires a more restricted meaning. With respect toelements described as one or more within a set, it should be understoodthat all combinations within the set are contemplated. If aspects of thedisclosure are described as “comprising” a feature, embodiments also arecontemplated “consisting of” or “consisting essentially of” the feature.Additional features and variations of the disclosure will be apparent tothose skilled in the art from the entirety of this application, and allsuch features are intended as aspects of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a representative multi-compartment syringe device forgenerating and delivering a surgical sealant and adhesive compositionaccording to the disclosure.

FIG. 1B shows the representative multi-compartment syringe device ofFIG. 1A in further combination with an applicator for delivering thesurgical sealant and adhesive composition to a site, for example, abiological tissue, where the composition is needed.

FIG. 2 is a schematic drawing showing the 2×2 matrix defined forapplication of Coseal® surgical sealant (Baxter International) with DOPA(“Coseal DOPA (+)”) and Coseal® surgical sealant without DOPA (“CosealDOPA (−)”) onto wet and dry surfaces.

FIG. 3A is a schematic drawing of an adhesive layer demonstrating pooradhesion to a liver surface.

FIG. 3B is a schematic drawing of an adhesive layer demonstrating strongadhesion to a liver surface.

FIG. 4A is a photograph of Coseal DOPA (−) applied on a dry surface.

FIG. 4B is a photograph of Coseal DOPA (+) applied on a dry surface.

FIG. 4C is a photograph of Coseal DOPA (−) applied on a wet surface.

FIG. 4D is a photograph of Coseal DOPA (+) applied on a wet surface.

FIG. 5A is a photograph of Coseal DOPA (−) applied on a dry surface.

FIG. 5B is a photograph of Coseal DOPA (−) applied on a surface wettedwith L-DOPA solution.

DETAILED DESCRIPTION

The present disclosure provides surgical adhesives and sealants suitablefor application to wet surfaces. Surgical adhesives and sealants aredescribed, for example, in U.S. Pat. Nos. 6,312,725, 6,624,245,6,911,496, 8,067,031, 8,460,708, and 8,481,073, which are herebyincorporated by reference in their entireties.

The surgical adhesives and sealants disclosed herein including L-DOPAadvantageously demonstrated adhesion to both dry and wet surfaces. Inparticular, the surgical adhesives and sealants disclosed hereindemonstrate improved adhesion to wet surfaces as compared to a surgicaladhesive or sealant that does not contain L-DOPA.

Dry Powder Composition

The present disclosure provides a dry powder composition that containsat least two biocompatible, non-immunogenic components having reactivegroups thereon, with the functional groups selected so as to enablereaction between the components, i.e., crosslinking, to form athree-dimensional matrix. Each component has a polymer core substitutedwith reactive groups. The dry powder composition contains a firstcomponent having a polymer core substituted with nucleophilic groups(e.g., amino groups or thiol groups) and a second component having apolymer core substituted with electrophilic groups (e.g., succinimidylgroups). Dry powder compositions having more than two components alsoare encompassed, where additional components may have nucleophilic orelectrophilic groups.

The reactive groups are selected so that the components are essentiallynon-reactive in a dry environment, for example, when the componenthaving a polymer core substituted with nucleophilic groups and thecomponent having a polymer core substituted with electrophilic groupsare formulated as and/or provided as a homogeneous dry powder. Uponexposure to an aqueous environment, the components are rendered reactiveand a plurality of components are then able to react in the aqueousenvironment to form a three-dimensional matrix. This matrix ispreferably formed without input of any external energy, for example, atroom temperature or at slightly elevated temperature.

The composition is particularly suitable for application involvingcontact between a biological system and the composition and/or thethree-dimensional matrix formed therefrom. The biological system can bea biological tissue, and in a preferred embodiment, is living tissue.

The resulting three-dimensional matrix is useful in a variety ofcontexts, and is particularly useful as a biomaterial for medicalapplications, such as for bioadhesion, tissue augmentation, tissuesealing, vascular sealing, needle hole sealing, hemostasis, and theprevention of adhesions following a surgical procedure or injury, forexample.

In one embodiment, substantially immediately or immediately uponexposure to the aqueous environment, the reactive groups on thecomponents of the composition begin to react and form athree-dimensional matrix. The term “substantially immediately” isintended to mean within less than five minutes, preferably within lessthan two minutes, and the term “immediately” is intended to mean withinless than one minute, preferably within less than 30 seconds. Typically,the three-dimensional composition will be completely formed within about30 minutes.

The homogeneous dry powder composition is comprised of: a firstcomponent having a polymeric core substituted with nucleophilic groups(e.g., amino groups or thiol groups) and a second component having apolymeric core substituted with electrophilic groups (e.g., succinimidylgroups). The nucleophilic and electrophilic groups are non-reactive withone another when the first and second components are admixed in a dryenvironment but are rendered reactive upon exposure to an aqueousenvironment such that the components react in the aqueous environment toform a three-dimensional matrix. In some cases, the nucleophilic andelectrophilic groups are relatively non-reactive with one another in anaqueous environment having an acidic pH, but are rendered reactive uponexposure to an aqueous environment having a basic pH. In order for athree-dimensional matrix to be formed, there is a plurality of reactivegroups present in each of the first and second components. In apreferred embodiment, one component has a polymeric core substitutedwith two or more (e.g., 3, 4, 5, 6, 7, or 8) nucleophilic groups, andthe other component has a polymeric core substituted with two or more(e.g., 3, 4, 5, 6, 7, or 8) electrophilic groups. The homogeneous drypowder composition optionally includes L-DOPA.

The selection of electrophilic groups provided on the second componentis made so that reaction is possible with the specific nucleophilicgroups on the first component. Thus, when the nucleophilic groups aresulfhydryl moieties, the electrophilic groups are selected so as toreact with sulfhydryl moieties. Suitable sulfhydryl-reactive groupsinclude, but are not limited to, mixed anhydrides; ester derivatives ofphosphorus; ester derivatives of p-nitrophenol, p-nitrothiophenol andpentafluorophenol; esters of substituted hydroxylamines, includingN-hydroxyphthalimide esters, N-hydroxysuccinimide esters,N-hydroxysulfosuccinimide esters, and N-hydroxyglutarimide esters;esters of 1-hydroxybenzotriazole;3-hydroxy-3,4-dihydro-benzotriazin-4-one;3-hydroxy-3,4-dihydro-quinazoline-4-one; carbonylimidazole derivatives;acid chlorides; ketenes; isocyanates; maleimides; substitutedmaleimides; haloalkanes; epoxides; imines; aziridines; olefins(including conjugated olefins) such as ethenesulfonyl, etheneimino,acrylate, methacrylate, and α,β-unsaturated aldehydes and ketones; andcombinations thereof.

Examples of sulfhydryl-reactive groups include, but are not limited to,

The polymer core of each component comprises a polymer to which thereactive groups are bound. Suitable polymers include, but are notlimited to, polyalkylene oxides, particularly polyethylene glycol (PEG)and poly(ethylene oxide)-poly(propylene oxide) copolymers, includingblock and random copolymers; polyols such as glycerol, polyglycerol(PG), particularly highly branched polyglycerol, and propylene glycol;poly(oxyalkylene)-substituted diols, and poly(oxyalkylene)-substitutedpolyols such as mono-, di- and tri-polyoxyethylated glycerol, mono- anddi-polyoxyethylated propylene glycol, and mono- and di-polyoxyethylatedtrimethylene glycol; polyoxyethylated sorbitol, polyoxyethylatedglucose; poly(acrylic acids) and analogs and copolymers thereof, such aspolyacrylic acid per se, polymethacrylic acid,poly(hydroxyethylmethacrylate), poly(hydroxyethylacrylate),poly(methylalkylsulfoxide methacrylates), poly(methylalkylsulfoxideacrylates) and copolymers of any of the foregoing, and/or withadditional acrylate species such as aminoethyl acrylate andmono-2-(acryloxy)-ethyl succinate; polymaleic acid; poly(acrylamides)such as polyacrylamide per se, poly(methacrylamide),poly(dimethylacrylamide), poly(N-isopropyl-acrylamide), and copolymersthereof; poly(olefinic alcohols) such as poly(vinyl alcohols) andcopolymers thereof; poly(N-vinyl lactams) such as poly(vinylpyrrolidones), poly(N-vinyl caprolactams), and copolymers thereof;polyoxazolines, including poly(methyloxazoline) andpoly(ethyloxazoline); and polyvinylamines; as well as copolymers of anyof the foregoing.

Those of ordinary skill in the art will appreciate that syntheticpolymers such as polyethylene glycol cannot be prepared practically tohave exact molecular weights, and that the term “molecular weight” asused herein refers to the weight average molecular weight of a number ofmolecules in any given sample, as commonly used in the art. Thus, asample of PEG 2,000 might contain a statistical mixture of polymermolecules ranging in weight from, for example, 1,500 to 2,500 daltonswith one molecule differing slightly from the next over a range.Specification of a range of molecular weights indicates that the averagemolecular weight may be any value between the limits specified, and mayinclude molecules outside those limits. Thus, a molecular weight rangeof about 800 to about 20,000 indicates an average molecular weight of atleast about 800, ranging up to about 20 kDa.

Although a variety of different polymers can be used in the presentcompositions, as indicated above, preferred synthetic hydrophilicpolymers are PEG and PG, particularly highly branched PEG. Various formsof PEG are extensively used in the modification of biologically activemolecules because PEG lacks toxicity, antigenicity, and immunogenicity(i.e., is biocompatible), can be formulated so as to have a wide rangeof solubilities, and does not typically interfere with the enzymaticactivities and/or conformations of peptides. A particularly preferredpolymer for certain applications is a PEG having a molecular weightwithin the range of about 100 to about 100,000, although for highlybranched PEG, far higher molecular weight polymers can be employed, upto 1,000,000 or more, providing that biodegradable sites areincorporated ensuring that all degradation products will have amolecular weight of less than about 30,000. For most PEGs, however, thepreferred molecular weight is about 1,000 to about 20,000, morepreferably within the range of about 7,500 to about 20,000. Mostpreferably, the polyethylene glycol has a molecular weight ofapproximately 10,000.

Multi-functionalized forms of PEG are of particular interest andinclude, but are not limited to, PEG succinimidyl glutarate, PEGsuccinimidyl propionate, PEG succinimidyl butylate, PEG succinimidylacetate, PEG succinimidyl succinamide, PEG succinimidyl carbonate, PEGpropionaldehyde, PEG glycidyl ether, PEG-isocyanate, andPEG-vinylsulfone. Many such forms of PEG are described in U.S. Pat. Nos.5,328,955 and 6,534,591, which are hereby incorporated by reference intheir entireties. Various forms of multi-amino PEG are commerciallyavailable from sources such as PEG Shop, a division of SunBio of SouthKorea (www.sunbio.com), Nippon Oil and Fats (Yebisu Garden Place Tower,20-3 Ebisu 4-chome, Shibuya-ku, Tokyo), Nektar Therapeutics (San Carlos,Calif., formerly Shearwater Polymers, Huntsville, Ala.) and fromHuntsman's Performance Chemicals Group (Houston, Tex.) under the nameJeffamine® polyoxyalkyleneamines. Multi-amino PEGs include theJeffamine® diamines (“D” series) and triamines (“T” series), whichcontain two and three primary amino groups per molecule.Poly(sulfhydryl) PEGs are available from Nektar Therapeutics, e.g., inthe form of pentaerythritol poly(ethylene glycol) ether tetra-sulfhydryl(molecular weight 10,000). Various forms of multi-arm (e.g., 4-, 6-, and8-arm) PEG also are commercially available from sources such as CreativePEGWorks (Chapel Hill, N.C.) and Sigma-Aldrich (St. Louis, Mo.).

In an embodiment, the first component polymer core and second componentpolymer core are both branched poly(ethylene oxide). In an embodiment,the first component polymer core and second component polymer core areboth 4-arm poly(ethylene oxide). In an embodiment, the first componentpolymer core and second component polymer core are both 8-armpoly(ethylene oxide). In an embodiment, the first component polymer coreand second component polymer core are independently 4-arm poly(ethyleneoxide), 6-arm poly(ethylene oxide), and/or 8-arm poly(ethylene oxide).In an embodiment, the sulfhydryl-reactive groups are succinimidylgroups. In an embodiment, the dry powder composition comprises a 4-arm,succinimidyl-terminated poly(ethylene oxide) and a 4-arm,thiol-terminated poly(ethylene oxide). In an embodiment, the dry powdercomposition comprises an 8-arm, succinimidyl-terminated poly(ethyleneoxide) and an 8-arm, thiol-terminated poly(ethylene oxide). In anembodiment, the dry powder composition comprises an 8-arm,succinimidyl-terminated poly(ethylene oxide) and a 4-arm,thiol-terminated poly(ethylene oxide). In an embodiment, the dry powdercomposition comprises a 4-arm, succinimidyl-terminated poly(ethyleneoxide) and an 8-arm, thiol-terminated poly(ethylene oxide).

In an embodiment, the first component is

wherein PEG is poly(ethylene oxide). Each PEG independently includes anumber of ethylene oxide units, for example, 15 to 150, 30 to 100, 35 to90, 40 to 80, 45 to 70, 50 to 60, 54 to 58, 20 to 40, 40 to 60, 50 to80, and/or 80 to 130 ethylene oxide units.

In an embodiment, the second component is

wherein PEG is poly(ethylene oxide). Each PEG independently includes anumber of ethylene oxide units, for example, 15 to 150, 30 to 100, 35 to90, 40 to 80, 45 to 70, 50 to 60, 54 to 58, 20 to 40, 40 to 60, 50 to80, and/or 80 to 130 ethylene oxide units.

In an embodiment, the 4-arm, succinimidyl-terminated poly(ethyleneoxide) has a weight average molecular weight (M_(w)) of about 8 kDa toabout 14 kDa, such as about 9 kDa to about 13 kDa, about 10 kDa to about12 kDa, and/or about 11 kDa. In an embodiment, the 4-arm,thiol-terminated poly(ethylene oxide) has a weight average molecularweight (M_(w)) of about 7 kDa to about 13 kDa, such as about 8 kDa toabout 12 kDa, 9 kDa to about 11 kDa, and/or about 10 kDa.

Formation of the Three-Dimensional Matrix

A three-dimensional matrix is formed by: (a) providing a first componenthaving a polymeric core substituted with nucleophilic groups (e.g.,amino groups or thiol groups), a second component having a polymericcore substituted with electrophilic groups (e.g., succinimidyl groups),and L-DOPA; (b) rendering the nucleophilic and electrophilic groupsreactive by exposing the first component, second component, and L-DOPAto an aqueous environment having a pH sufficient to effect reaction; and(c) allowing a three-dimensional matrix to form. Typically, the matrixis formed, e.g., by polymerization, without input of any externalenergy.

In one embodiment, a three-dimensional matrix is formed by: (a)dissolving a dry powder composition comprising a first component havinga polymer core substituted with at least two sulfhydryl groups and asecond component having a polymer core substituted with at least twosulfhydryl-reactive groups in a first aqueous solution comprisingL-3,4-dihydroxyphenylalanine (L-DOPA) and having a pH of about 1 toabout 5.5 to form a homogeneous solution; (b) adding a second aqueoussolution having a pH of about 6 to about 11 to the homogeneous solutionto form a mixture; and (c) placing the mixture into contact with atissue surface and allowing a three-dimensional composition to form onthe tissue surface.

In one embodiment, a three-dimensional matrix is formed by: (a) treatinga tissue surface with a solution of L-DOPA to obtained a treated tissuesurface; (b) dissolving a dry powder composition comprising a firstcomponent having a polymer core substituted with at least two sulfhydrylgroups and a second component having a polymer core substituted with atleast two sulfhydryl-reactive groups in a first aqueous solution havinga pH of about 1 to about 5.5 to form a homogeneous solution; (c) addinga second aqueous solution having a pH of about 6 to about 11 to thehomogeneous solution to form a mixture; and (d) placing the mixture intocontact with the treated tissue surface and allowing a three-dimensionalcomposition to form on the treated tissue surface.

The first and second components of the dry powder composition aretypically combined in amounts such that the number of nucleophilicgroups (e.g., amino groups or thiol groups) in the mixture isapproximately equal to the number of electrophilic groups (e.g.,succinimidyl groups) in the mixture. As used in this context, the term“approximately” refers to a 2:1 to 1:2 ratio of moles of nucleophilicgroups to moles of electrophilic groups. A 1:1 molar ratio ofnucleophilic to electrophilic groups is generally preferred.

The first and second components are blended together to form ahomogeneous dry powder. This powder is then combined with an aqueoussolution having a pH within the range of about 1.0 to 5.5, such as about1.2 to about 5, about 1.4 to about 4.5, about 1.5 to about 4, about 1.6to about 3.5, about 1.7 to about 3, about 1.8 to about 2.7, about 1.9 toabout 2.5, about 2 to about 2.4, and/or about 2.1 to about 2.3, to forma homogeneous acidic aqueous solution, and this solution is thencombined with an aqueous solution having a pH within the range of about6.0 to 11.0, such as about 7 to about 10.5, such as about 8 to about 10,about 9 to about 10, about 9.3 to about 10, about 9.5 to about 9.9,about 9.6 to about 9.8, about 9.65 to about 9.75, and/or about 9.7, toform a reactive solution.

The acidic aqueous solutions having a pH within the range of about 1.0to 5.5, include by way of illustration and not limitation, solutions of:citric acid, hydrochloric acid, phosphoric acid, sulfuric acid,3-[(1,1-dimethyl-2-hydroxyethyl)amino]-2-hydroxypropanesulfonic acid(AMPSO), acetic acid, lactic acid, and combinations thereof. In apreferred embodiment, the acidic aqueous solution is a solution ofcitric acid, hydrochloric acid, phosphoric acid, sulfuric acid, andcombinations thereof.

Regardless of the precise acidifying agent, the acidic solutionpreferably has a pH such that it retards the reactivity of thenucleophilic groups on the first component. For example, a pH of 2.1 isgenerally sufficient to retard the nucleophilicity of thiol groups. Anexemplary acidic solution is a solution of hydrochloric acid, having aconcentration of about 6.3 mM and a pH in the range of 2.1 to 2.3. Thissolution may be prepared by combining concentrated hydrochloric acidwith water, i.e., by diluting concentrated hydrochloric acid with water.

Basic aqueous solutions having a pH within the range of about 6.0 to11.0, include by way of illustration and not limitation, solutions of:glutamate, acetate, carbonate and carbonate salts (e.g., sodiumcarbonate, sodium carbonate monohydrate and sodium bicarbonate), borate,phosphate and phosphate salts (e.g., monobasic sodium phosphatemonohydrate and dibasic sodium phosphate), and combinations thereof. Ina preferred embodiment, the basic aqueous solution is a solution ofcarbonate salts, phosphate salts, and combinations thereof.

In general, the basic solution is an aqueous solution that neutralizesthe effect of the acidic solution, when it is added to the homogeneoussolution of the first and second components and the acid solution, sothat the nucleophilic groups of the first component regain theirnucleophilic character (that has been masked by the action of the acidicsolution), thus allowing the nucleophilic groups to react with theelectrophilic groups of the second component. An exemplary basicsolution is an aqueous solution of carbonate and phosphate salts, e.g.,sodium phosphate and sodium carbonate.

In an embodiment, the three-dimensional matrix comprises a crosslinkedpolymeric material having a structure:

wherein each n is independently 15 to 150, 30 to 100, 35 to 90, 40 to80, 45 to 70, 50 to 60, 54 to 58, 20 to 40, 40 to 60, 50 to 80, and/or80 to 130; and each m is independently 15 to 150, 30 to 100, 35 to 90,40 to 80, 45 to 70, 50 to 60, 54 to 58, 20 to 40, 40 to 60, 50 to 80,and/or 80 to 130. In the formula above, use of the symbol

indicates that the molecular structure beyond this point is unspecifiedcrosslinked material generally formed by reaction of the firstcomponent, the second component, and L-DOPA as described herein. Theformula above is a representative example of a structure generallyformed by reaction of a 4-arm, sulfhydryl-reactive group-terminatedpoly(ethylene oxide), a 4-arm, thiol-terminated poly(ethylene oxide),and L-DOPA as described herein.

In an embodiment, the three-dimensional matrix comprises a crosslinkedpolymeric material having a structure:

wherein L is null, —(CH₂)₁₋₅—, —CO(CH₂)₁₋₅—, —NHCO(CH₂)₁₋₅—, or—(CH₂)₁₋₅NHCO(CH₂)₁₋₅—; each n is independently 15 to 150, 20 to 40, 40to 60, 50 to 80, and/or 80 to 130; and each m is independently 15 to150, 20 to 40, 40 to 60, 50 to 80, and/or 80 to 130. In the formulaabove, use of the symbol

indicates that the molecular structure beyond this point is unspecifiedcrosslinked material generally formed by reaction of the firstcomponent, the second component, and L-DOPA as described herein. Theformula above is a representative example of a structure generallyformed by reaction of an 8-arm, sulfhydryl-reactive group-terminatedpoly(ethylene oxide), an 8-arm, thiol-terminated poly(ethylene oxide),and L-DOPA as described herein.

In an embodiment, the three-dimensional matrix comprises a crosslinkedpolymeric material having a structure:

wherein L is null, —(CH₂)₁₋₅—, —CO(CH₂)₁₋₅—, —NHCO(CH₂)₁₋₅—, or—(CH₂)₁₋₅NHCO(CH₂)₁₋₅—; each n is independently 15 to 150, 20 to 40, 40to 60, 50 to 80, and/or 80 to 130; and each m is independently 15 to150, 20 to 40, 40 to 60, 50 to 80, and/or 80 to 130. In the formulaabove, use of the symbol

indicates that the molecular structure beyond this point is unspecifiedcrosslinked material generally formed by reaction of the firstcomponent, the second component, and L-DOPA as described herein. Theformula above is a representative example of a structure generallyformed by reaction of an 8-arm, sulfhydryl-reactive group-terminatedpoly(ethylene oxide), an 8-arm, thiol-terminated poly(ethylene oxide),and L-DOPA as described herein.

In an embodiment, the three-dimensional matrix is prepared by reacting acomponent having a polymer core substituted with at least two (e.g., 3,4, 5, 6, 7, or 8) sulfhydryl-reactive groups with (i) L-DOPA and (ii) acomponent having a polymer core substituted with at least two (e.g., 3,4, 5, 6, 7, or 8) sulfhydryl groups.

Delivery Systems

Multi-Compartment Devices: Suitable delivery systems for the homogeneousdry powder composition and the two aqueous solutions may involve amulti-compartment device, where one or more compartments contain thepowder and one or more compartments contain the aqueous solutions neededto provide for the aqueous environment, such that the dry powdercomposition can be exposed to the aqueous environment as it leaves itsrespective compartment. Many devices that are adapted for delivery ofmulti-component tissue sealants/hemostatic agents are well known in theart and can also be used. Alternatively, the dry powder composition canbe delivered using any type of controllable extrusion system, or it canbe delivered manually in the form of a dry powder, and exposed to theaqueous environment at the site of administration.

The homogeneous dry powder composition and the two aqueous solutions maybe conveniently formed under aseptic conditions by placing each of thethree ingredients (dry powder, acidic solution and basic solution) intoseparate syringe barrels. For example, the dry powder composition, firstaqueous solution and second aqueous solution can be housed separately ina multiple-compartment syringe system having multiple syringe barrels, amixing head, and an exit orifice. The first aqueous solution can beadded to the syringe barrel housing the dry powder composition todissolve the dry powder composition and form a homogeneous solution,which is then extruded into the mixing head. The second aqueous solutioncan be simultaneously extruded into the mixing head. Finally, theresulting composition can then be extruded through the orifice onto asurface.

For example, the syringe barrels holding the dry powder and the basicsolution may be part of a dual-syringe system, e.g., a double barrelsyringe as described in U.S. Pat. No. 4,359,049, which is herebyincorporated by reference in its entirety. In this embodiment, the acidsolution can be added to the syringe barrel that also holds the drypowder, so as to produce the homogeneous solution. In other words, theacid solution may be added (e.g., injected) into the syringe barrelholding the dry powder to thereby produce a homogeneous solution of thefirst and second components. This homogeneous solution can then beextruded into a mixing head, while the basic solution is simultaneouslyextruded into the mixing head. Within the mixing head, the homogeneoussolution and the basic solution are mixed together to thereby form areactive mixture. Thereafter, the reactive mixture is extruded throughan orifice and onto a surface (e.g., tissue), where a film is formed,which can function as a sealant or a barrier, or the like. The reactivemixture begins forming a three-dimensional matrix immediately upon beingformed by the mixing of the homogeneous solution and the basic solutionin the mixing head. Accordingly, the reactive mixture is preferablyextruded from the mixing head onto the tissue very quickly after it isformed so that the three-dimensional matrix forms on, and is able toadhere to, the tissue.

A preferred embodiment of a multi-compartment syringe system is shown inFIG. 1A. As shown, the device is comprised of three syringes, with firstand second syringes 1, 2 of the multi-compartment syringe device 10containing the two aqueous solutions and the third syringe 3 containingthe dry powder composition. The two syringes 1, 2, containing thesolutions are pre-assembled into a syringe housing 4 with a transferport closure adapter 5 attached to the housing assembly 4 to allowmixing of the dry powder into the correct syringe. A syringe clip 6 canbe uncoupled from one of the syringes and remain attached to the plungerrod of the syringe that does not require mixing with the dry powdercomposition, so as to facilitate separate, independent movement of aplunger (and thus the contents) of the first syringe 1. In thisembodiment, the acid solution (with or without L-DOPA) contained in thefirst syringe 1 is injected into the syringe barrel 3 holding the drypowder to thereby produce a homogeneous solution of the first and secondcomponents, and optionally L-DOPA. As shown in FIG. 1A, the syringe clip6 can be coupled to both of the syringe plungers of the first and secondsyringes 1, 2, so as to facilitate substantially simultaneous flow ofthe homogeneous solution contained in the first syringe 1 and the basicsolution contained in the second syringe 2 into a mixing head to therebyform a reactive mixture. The reactive mixture can then be delivered viaan orifice onto a surface (e.g., tissue), where a film capable offunctioning as a sealant, adhesive, barrier, or the like, can be formed.As shown in FIG. 1B, the empty third syringe 3 can be detached from thefirst syringe 1 and an applicator 7 attached onto the end of the syringehousing 4. Suitable delivery devices include the delivery devicescurrently used to deliver Coseal® surgical sealant compositions as shownin the packaging insert for this product.

Other systems for combining two reactive liquids are well known in theart, and include the systems described in U.S. Pat. Nos. 6,454,786,6,461,325, 5,585,007, 5,116,315, and 4,631,055; and U.S. PatentApplication Publication No. 2004/0068266, each of which is herebyincorporated by reference in its entirety.

Pressurized Delivery Devices: Other delivery systems for dispensing themulticomponent compositions disclosed herein may include pressurizeddelivery devices, examples of which are described in U.S. PatentApplication Publication No. 2006/0071025, which is hereby incorporatedby reference in its entirety. Such a pressurized delivery device mayinclude a diffuser surface having an outlet extending therethrough thatis positioned downstream from a plurality of inlets. While at least oneinlet is adapted to communicate with a source of a pressurized carrierfluid, each of a plurality of inlets is adapted to communicate with asource of a different fluid component. Using this device, the dry powdersolution is premixed with the first acidic aqueous solution, in someembodiments as described above the first acidic solution may furthercontain L-DOPA, to form a homogeneous solution as previously describedand this solution is subsequently communicated as a first fluidcomponent. The second alkaline aqueous buffer solution as describedabove is communicated as the second fluid component. Once the diffusersurface receives fluid components from the inlets, each received fluidcomponent is pushed toward the outlet for mixing and dispensingtherethrough by the pressurized carrier fluid, typically a gas such asair, from the carrier fluid inlet. The diffuser surface and the inletsmay represent components of a mixing nozzle.

In general, there are two categories of gas enhanced nozzles fordispensing reactive components of a multicomponent composition—thosethat involve internal mixing and those that involve external mixing.When the diffuser surface is a part of a nozzle, the nozzle may beconsidered an internal-mixing nozzle. Unlike other internal-mixingtechnologies, the internal-mixing nozzle of the pressurized deliverydevice disclosed herein provides several features that serveindividually and collectively to eliminate clogging. For example, adiffuser surface typically has a shape effective to direct and maintaineach received fluid component in a different flow path on the diffusersurface toward the outlet for mixing therein and dispensingtherethrough. Due to the minimal residence time of the mixture withinthe nozzle, reactive components do not have time to set and clog thenozzle before the mixture is forced out of the nozzle by the pressurizedcarrier fluid. In addition, the outlet may be aligned with any or all ofthe carrier fluid inlets that may be present in the nozzle to direct thepressurized carrier fluid in a manner that enhances fluid componentmixing and to expel the mixture in a jet like manner. As the orientationof the diffuser surface relative to the inlets affects the performanceof the device, the diffuser surface may be permanently affixed orimmobilized with respect to the inlets; however, when the diffusersurface is detachable from the inlets, the nozzle may be disassembled tofacilitate cleaning and/or replacement of parts. For example, thediffuser surface may be replaceable/and or disposable. Additionally,when the pressurized delivery device disclosed herein has a diffusersurface that is detachable from the inlets, the device may beconstructed to allow assembly of the components in only configurationsthat align the diffuser surface to the inlets such that the performanceof the device is optimized.

Kits

The compositions disclosed herein can be packaged in kits and used in avariety of medical applications. The kit would include aqueoussolutions, as well as written or otherwise illustrated instructions foruse. A typical kit for use in medical applications, comprises: (a) ahomogeneous dry powder composition comprised of: (i) a first componenthaving a polymer core substituted with at least two sulfhydryl groups;and (ii) a second component having a polymer core substituted with atleast two sulfhydryl-reactive groups; (b) a first aqueous solutioncomprising L-3,4-dihydroxyphenylalanine (L-DOPA) and having a pH ofabout 1 to 5.5; and (c) a second aqueous solution having a pH of about 6to 11; wherein each component is packaged separately and admixedimmediately prior to use. As is evident to those of ordinary skill inthe art, prior to use, each component should be packaged separately suchthat the component remains sterile and does not contact anothercomponent. As an example, two of the individual components can bepackaged in separate sterile packages such as separate syringe barrelsof a multiple-compartment syringe system having multiple syringe barrelsas described above.

Another typical kit for use in medical applications, comprises: (a) adry powder composition comprised of: (i) a first component having apolymer core substituted with at least two sulfhydryl groups; and (ii) asecond component having a polymer core substituted with at least twosulfhydryl-reactive groups; (b) a first aqueous solution having a pH ofabout 1 to about 5.5; (c) a second aqueous solution having a pH of about6 to about 11; and (d) L-3,4-dihydroxyphenylalanine (L-DOPA); whereineach component is packaged separately such that the component remainssterile and does not contact another component. In an embodiment, L-DOPAis provided as a powder. In an embodiment, L-DOPA is provided as anaqueous solution, such as a pre-filled syringe or a vial As is evidentto those of ordinary skill in the art, prior to use, each componentshould remain in a separate sterile package.

In another embodiment, the kit further comprises a delivery system thatwill allow the surgical sealant and/or adhesive composition to bedelivered as a spray. The spray can be generated by manually mixing thecomponents and passing them through a spray nozzle. The spray generationcan also be accomplished by using a flow of gas (for example, air,nitrogen, carbon dioxide). Suitable delivery devices that may beincluded in the kits include the multi-compartment syringe device and/orthe pressurized delivery devices described herein.

In one embodiment of the kit, a multi-compartment device is included inthe kit. As previously described, the multi-compartment device may be amultiple-compartment syringe device having multiple barrels, a mixinghead, and an exit orifice, wherein the dry powder composition, the firstaqueous solution, and the second aqueous solution are housed separatelyin the multiple-compartment syringe device.

In another embodiment of the kit, a pressurized delivery device isincluded in the kit. As previously described, the pressurized deliverydevice includes a plurality of fluid component inlets each adapted tocommunicate with a source of different fluid components; at least onecarrier fluid inlet adapted to communicate with a source of apressurized carrier fluid; a diffuser surface located downstream fromthe plurality of fluid component inlets and the at least one carrierfluid inlet; and an outlet extending through the diffuser surface,wherein the diffuser surface is adapted to receive fluid componentsthereon and has a shape effective to direct and maintain each receivedfluid component in a different flow path toward the outlet for mixingand dispensing therethrough by the pressurized carrier fluid from the atleast one carrier fluid inlet.

Suitable kits are not limited to the devices described herein and mayalso include any other suitable delivery device known in the art of drugdelivery.

Uses

The surgical sealant and adhesive compositions disclosed herein can beused in a variety of different applications. In general, thesecompositions can be adapted for use in any tissue engineeringapplication where synthetic gel matrices are currently being utilized.For example, the compositions are useful as tissue sealants andadhesives, vascular sealants, in tissue augmentation, in tissue repair,as hemostatic agents, and in preventing tissue adhesions, and may beused in a variety of open, endoscopic, and laparoscopic surgicalprocedures. One of skill in the art can easily determine the appropriateadministration protocol to use with any particular composition having aknown gel strength and gelation time.

In one application, the compositions described herein can be used formedical conditions that require a coating or sealing layer to preventthe leakage of gases, liquid or solids.

Methods of use typically entail applying the composition to the damagedtissue or organ to seal 1) vascular and or other tissues or organs tostop or minimize the flow of blood; 2) thoracic tissue to stop orminimize the leakage of air; 3) gastrointestinal tract or pancreatictissue to stop or minimize the leakage of fecal or tissue contents; 4)bladder or urethra to stop or minimize the leakage of urine; 5) dura tostop or minimize the leakage of cerebrospinal fluid; and/or 6) skin orserosal tissue to stop the leakage of serosal fluid. These compositionsmay also be used to adhere tissues together such as small vessels,nerves or dermal tissue. The compositions can be used 1) by applyingthem to the surface of one tissue and then a second tissue may berapidly pressed against the first tissue or 2) by bringing the tissuesin close juxtaposition and then applying the compositions such that boththe first and second tissues are contacted with the compositions. Inaddition, the compositions can be used to fill spaces in soft and hardtissues that are created by disease or surgery.

Therefore, one embodiment is a method of sealing tissue of a patientcomprising the steps of: (a) providing a first component having apolymeric core substituted with nucleophilic groups (e.g., amino groupsor thiol groups), a second component having a polymeric core substitutedwith electrophilic groups (e.g., succinimidyl groups), and L-DOPA; (b)rendering the nucleophilic and electrophilic groups reactive by exposingthe first component, second component, and L-DOPA to an aqueousenvironment having a pH sufficient to effect reaction; and (c) placingthe mixture into contact with tissue and allowing a three-dimensionalmatrix to form and seal the tissue.

In another embodiment, the surgical adhesive and/or sealant compositionscan be applied in conjunction with an implanted medical device such thatit prevents the leakage of gases, liquids or solids from the device orfrom the device-tissue interface. For example, following theimplantation of a vascular graft (either synthetic or biological), thereis often leakage of blood through the suture holes in the graft or atthe interface between the graft and the tissue. The surgical adhesiveand/or sealant composition disclosed herein can be applied to this areato prevent further blood leakage.

In an embodiment, a method of sealing tissue of a patient comprises: (a)dissolving a dry powder composition comprising a first component havinga polymer core substituted with at least two sulfhydryl groups and asecond component having a polymer core substituted with at least twosulfhydryl-reactive groups in a first aqueous solution comprisingL-3,4-dihydroxyphenylalanine (L-DOPA) and having a pH of about 1 toabout 5.5 to form a homogeneous solution; (b) adding a second aqueoussolution having a pH of about 6 to about 11 to the homogeneous solutionto form a mixture; and (c) placing the mixture into contact with atissue surface and allowing a three-dimensional composition to form onthe tissue surface.

In an embodiment, a method of sealing tissue of a patient comprises: (a)treating a tissue surface with a solution of L-DOPA to obtained atreated tissue surface; (b) dissolving a dry powder compositioncomprising a first component having a polymer core substituted with atleast two sulfhydryl groups and a second component having a polymer coresubstituted with at least two sulfhydryl-reactive groups in a firstaqueous solution having a pH of about 1 to about 5.5 to form ahomogeneous solution; (c) adding a second aqueous solution having a pHof about 6 to about 11 to the homogeneous solution to form a mixture;and (d) placing the mixture into contact with the treated tissue surfaceand allowing a three-dimensional composition to form on the treatedtissue surface.

EXAMPLES Example 1

An L-DOPA-containing surgical adhesive was prepared using a 2 mL Coseal®Surgical Sealant (Baxter International) (“Coseal”) kit composed of twosynthetic polyethylene glycols (PEGs), a dilute hydrogen chloridesolution and a sodium phosphate/sodium carbonate buffer solution. Toprepare an L-DOPA solution, the syringe of the Coseal® kit containingdiluted hydrochloric acid was removed, and the diluted hydrochloric acidsolution was poured out of the syringe and precisely weighed. L-DOPA wasadded to the diluted hydrochloric acid solution in an appropriate amountto obtain an L-DOPA concentration of 3 to 5 mg/g of solution. For theadhesion experiments described below, the mass of the solution was 498.9mg and the mass of L-DOPA was 1.6 mg, corresponding to an L-DOPAconcentration of 3.2 mg/g. After the L-DOPA powder was completelydissolved, the solution was aspirated back into the syringe, which wasthen placed back in the syringe holder device.

To assess adhesion of the L-DOPA-containing surgical adhesive on a wetsurface, the Coseal® sealant with added L-DOPA (referred to as “CosealDOPA (+)”) and unmodified Coseal® (referred to as “Coseal DOPA (−)”)were applied to dry and wet areas of a slice of beef liver. The slice ofliver was set on the bench and an area was defined for application ofCoseal DOPA (+) and Coseal DOPA (−) onto wet and dry surfaces in a 2×2matrix as shown in FIG. 2.

Half of the area (quadrants 2 and 4, as shown in FIG. 2) were wettedwith distilled water while avoiding contamination and wetting of the dryareas (quadrants 1 and 3, as shown in FIG. 2). Excess water was removedby hanging the slice of liver vertically for a few seconds. Equalvolumes of Coseal DOPA (+) and (−) were then applied onto the wet andthe dry areas of the slice of liver. The applied adhesives were allowedto polymerize for a minimum of 5 minutes.

The adhesiveness of Coseal DOPA (+) and (−) under dry and wet conditionswas assessed by using tweezers to peel off and lift up the polymerizedadhesive layer. The tweezers were gently introduced between the liverand the adhesive layer and lifted to assess the adhesiveness of theadhesive layer on the liver surface as shown in FIGS. 3A and 3B. Theresults of the adhesiveness assessment are shown in FIG. 4A (Coseal DOPA(−) applied on dry surface), FIG. 4B (Coseal DOPA (+) applied on drysurface), FIG. 4C (Coseal DOPA (−) applied on wet surface), and FIG. 4D(Coseal DOPA (+) applied on wet surface).

As shown in FIG. 4A, Coseal DOPA (−) demonstrated adhesion to a drysurface, with the adhesive material being only partially torn apart fromthe liver surface while some material remained on the liver tissue. Asshown in FIG. 4C, Coseal DOPA (−) demonstrated poor adhesion to a wetsurface, with the adhesive layer being lifted up and removed from thesurface. As shown in FIG. 4B and FIG. 4D, Coseal DOPA (+) advantageouslydemonstrated adhesion to both dry and wet surfaces, in particulardemonstrating significantly improved adhesion to wet surfaces.

Example 2

The adhesion of unmodified Coseal® surgical sealant to a surface treatedwith a spray of an L-DOPA solution was assessed according to thefollowing procedure. An L-DOPA solution was prepared by dissolving about6 mg of L-DOPA in 2 mL of water, and then aspirating the solution into asyringe. Coseal® surgical sealant was prepared according to themanufacturer's instructions. A slice of beef liver was divided into twoareas: a dry area and a wet area that was wetted and thereby “primed”with the L-DOPA solution using a 21G needle. Equal volumes of Coseal®were then applied to the dry area and to the area having been treatedwith the L-DOPA solution. The applied adhesive was allowed to cure for 5minutes.

The adhesiveness was then assessed by using tweezers to peel off andlift up the polymerized adhesive layers. The tweezers were gentlyintroduced between the liver and the adhesive layer and lifted to assessthe adhesiveness of the adhesive layer on the liver surface. The resultsof the adhesiveness assessment are shown in FIG. 5A (dry surface) andFIG. 5B (surface wetted with L-DOPA).

As shown in FIG. 5A and FIG. 5B, Coseal® demonstrated significantlyimproved adhesion when applied to a surface that had been treated withan L-DOPA solution compared to a dry surface.

The present invention is described in connection with preferredembodiments. However, it should be appreciated that the invention is notlimited to the disclosed embodiments. It is understood that, given thedescription of the embodiments of the invention herein, variousmodifications can be made by a person skilled in the art. Suchmodifications are encompassed by the claims below.

What is claimed is:
 1. A kit comprising: (a) a dry powder compositioncomprising a first component having a polymer core substituted with atleast two sulfhydryl groups and a second component having a polymer coresubstituted with at least two sulfhydryl-reactive groups; (b) a firstaqueous solution comprising L-3,4-dihydroxyphenylalanine (L-DOPA) andhaving a pH of about 1 to about 5.5; and (c) a second aqueous solutionhaving a pH of about 6 to about 11; wherein each of (a), (b), and (c) ispackaged separately prior to use.
 2. The kit of claim 1, wherein thefirst component polymer core and second component polymer core are bothbranched poly (ethylene oxide).
 3. The kit of claim 1, wherein thesulfhydryl-reactive groups are succinimidyl groups.
 4. The kit of claim1, wherein the dry powder composition comprises a 4-arm,succinimidyl-terminated poly (ethylene oxide) and a 4-arm,thiol-terminated poly(ethylene oxide).
 5. The kit of claim 1, whereinthe dry powder composition comprises an 8-arm, succinimidyl-terminatedpoly(ethylene oxide) and an 8-arm, thiol-terminated poly(ethyleneoxide).
 6. The kit of claim 1, wherein the dry powder compositioncomprises (i) an 8-arm, succinimidyl-terminated poly(ethylene oxide) anda 4-arm, thiol-terminated poly(ethylene oxide); or (ii) a 4-arm,succinimidyl-terminated poly(ethylene oxide) and an 8-arm,thiol-terminated poly(ethylene oxide).
 7. The kit of claim 1, whereinthe first component is

wherein PEG is poly(ethylene oxide).
 8. The kit of claim 1, wherein thesecond component is

wherein PEG is poly(ethylene oxide).
 9. The kit of claim 1, furthercomprising a delivery device.
 10. The kit of claim 9, wherein thedelivery device is a multi-compartment syringe device or a pressurizeddelivery device.
 11. A surgical adhesive or sealant compositioncomprising a crosslinked polymeric material having a structure:

wherein each n is independently 15 to 150; and each m is independently15 to
 150. 12. A surgical adhesive or sealant composition prepared byreacting a component having a polymer core substituted with at least twosulfhydryl-reactive groups with (i) L-DOPA and (ii) a component having apolymer core substituted with at least two sulfhydryl groups.
 13. A kitcomprising: (a) a dry powder composition comprising a first componenthaving a polymer core substituted with at least two sulfhydryl groupsand a second component having a polymer core substituted with at leasttwo sulfhydryl-reactive groups; (b) a first aqueous solution having a pHof about 1 to about 5.5; (c) a second aqueous solution having a pH ofabout 6 to about 11; and (d) L-3,4-dihydroxyphenylalanine (L-DOPA);wherein each of (a), (b), (c), and (d) is packaged separately prior touse.
 14. The kit of claim 13, wherein the sulfhydryl-reactive groups aresuccinimidyl groups.
 15. The kit of claim 13, wherein the dry powdercomposition comprises a 4-arm, succinimidyl-terminated poly(ethyleneoxide) and a 4-arm, thiol-terminated poly(ethylene oxide).
 16. The kitof claim 13, wherein the dry powder composition comprises an 8-arm,succinimidyl-terminated poly(ethylene oxide) and an 8-arm,thiol-terminated poly(ethylene oxide).
 17. The kit of claim 13, whereinthe dry powder composition comprises (i) an 8-arm,succinimidyl-terminated poly(ethylene oxide) and a 4-arm,thiol-terminated poly(ethylene oxide); or a 4-arm,succinimidyl-terminated poly(ethylene oxide) and an 8-arm,thiol-terminated poly(ethylene oxide).
 18. The kit of claim 13, whereinthe first component is

wherein PEG is poly(ethylene oxide).
 19. The kit of claim 13, whereinthe second component is

wherein PEG is poly(ethylene oxide).
 20. The kit of claim 13, furthercomprising a delivery device.
 21. The kit of claim 20, wherein thedelivery device is a multi-compartment syringe device or a pressurizeddelivery device.
 22. The kit of claim 13, wherein the L-DOPA is providedas a powder.
 23. The kit of claim 13, wherein the L-DOPA is provided asan aqueous solution.
 24. The kit of claim 23, wherein the aqueoussolution of L-DOPA is provided as a pre-filled syringe or as a vial. 25.A method of sealing tissue of a patient comprising: (a) dissolving a drypowder composition comprising a first component having a polymer coresubstituted with at least two sulfhydryl groups and a second componenthaving a polymer core substituted with at least two sulfhydryl-reactivegroups in a first aqueous solution comprisingL-3,4-dihydroxyphenylalanine (L-DOPA) and having a pH of about 1 toabout 5.5 to form a homogeneous solution; (b) adding a second aqueoussolution having a pH of about 6 to about 11 to the homogeneous solutionto form a mixture; and (c) placing the mixture into contact with atissue surface and allowing a three-dimensional composition to form onthe tissue surface.
 26. A method of sealing tissue of a patientcomprising: (a) treating a tissue surface with a solution of L-DOPA toobtained a treated tissue surface; (b) dissolving a dry powdercomposition comprising a first component having a polymer coresubstituted with at least two sulfhydryl groups and a second componenthaving a polymer core substituted with at least two sulfhydryl-reactivegroups in a first aqueous solution having a pH of about 1 to about 5.5to form a homogeneous solution; (c) adding a second aqueous solutionhaving a pH of about 6 to about 11 to the homogeneous solution to form amixture; and (d) placing the mixture into contact with the treatedtissue and allowing a three-dimensional composition to form on thetreated tissue surface.